128 - Block deck face and 40`s jetting

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Abarthnorway - Remi L
Posts: 208
Joined: Sat Jun 24, 2006 2:39 pm
Location: Oslo, Norway
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128 - Block deck face and 40`s jetting

Post by Abarthnorway - Remi L » Wed Jul 17, 2013 11:19 pm

Hi Guy!


Sold on my 127 city car - awaiting a 128 Panorama in red - Bit more family friendly, and not to mention a stronger and sweeter engine to work on:-)

I have started to build an engine to suit the car - fast road spec - nothing fancy at all. All I want is a torquey 1300 with a wide usable power band. I started out with a low milage 128 Sport Coupe block that was dimensionally correct, but after honing reveiled some corrosion in two cylinders - ahhhhh - rebore and oversize pistons. Luckily I have a Ritmo 70 1299cc with 86.4 bore so this was stripped for its pistons, and after careful cleaning they seem ok for reuse.

128 Dimensional drawing.JPG
128 Dimensional drawing.JPG (39.32 KiB) Viewed 1322 times
The car in question looks like this....

Block pistons.jpg
Block pistons.jpg (37.07 KiB) Viewed 1322 times
Block on its way to machinist for rebore

Crank assembly.jpg
Crank assembly.jpg (36.44 KiB) Viewed 1322 times
Crank assembly in for balancing - perfect dimensionally

Mains oilway.jpg
Mains oilway.jpg (27.18 KiB) Viewed 1322 times
Big end oil.jpg
Big end oil.jpg (27.01 KiB) Viewed 1322 times

Modified oilways.....
I have been on this forum and read a couple of books - thanks!!!!

Waterway dent.jpg
Waterway dent.jpg (28.53 KiB) Viewed 1322 times
Dent in block waterway




Now to the questions:


1:
In the last picture You see a dent in the coolant gallery - the gasket firering is very close to the waterway..... my estimate is about 0.5 mm of gasket between the edge of the gallery to the firering...
CR will be approx 9.5:1
Problem???

bilde3.JPG
bilde3.JPG (115.4 KiB) Viewed 1322 times
I will use the black DCOE manifold for Solex 40 carbs.......

2:

Jetting:

1301 block
Flowed head - small 26*27 mm inlet port controlling section, valve + valveseat + deshroud.
Std 36/31 valves.
Approx 9.5:1 compression (Ritmo 1299 (55.4 stroke) 86,4 pistons with higher compression height 0.25 + 1 mm domed - original pistons already protude 0.1 due to block decked previously)
Std cam
Old Supersprint 4-2-1 manifold - runners combined length approx 32" - 32 mm ID primaries.
Solex 40 on DCOE manifold 29 chokes

Would You care to give a suitable jetting for this engine please?


Thank You!


Best regards

Remi Lovhoiden
GC_45

Guy Croft
Site Admin
Posts: 5025
Joined: Sun Jun 18, 2006 10:31 am
Location: Lincoln, UK
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Re: 128 - Block deck face and 40`s jetting

Post by Guy Croft » Thu Jul 18, 2013 2:48 pm

Hi Remi

don't worry about that dent!

40 carbs 29mm chokes my suggested jetting:

mains 125
air correctors 210
emulsion tube Solex A04
idle jet 40
pump jet 35-40

Hope this helps

G
Guy Croft, owner

Abarthnorway - Remi L
Posts: 208
Joined: Sat Jun 24, 2006 2:39 pm
Location: Oslo, Norway
Contact:

Re: 128 - Block deck face and 40`s jetting

Post by Abarthnorway - Remi L » Fri Jul 19, 2013 5:01 pm

Thank You!

I will give it a go.

Remi
GC_45

Guy Croft
Site Admin
Posts: 5025
Joined: Sun Jun 18, 2006 10:31 am
Location: Lincoln, UK
Contact:

Re: 128 - Block deck face and 40`s jetting

Post by Guy Croft » Fri Jul 19, 2013 9:45 pm

my pleasure Remi!

G
Guy Croft, owner

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